Self-propelled vehicle



' 1,639,536 Aug- 16, 2 1.. SAIVES SELF PROPELLED VEHICLE Filed April 1,1924 Patented Aug. 1 1927.

UNITED STATES PATENT OFFICE.

mow. snvns, or'nmmcoun'r; rmcn, assreuoa 'ro LOUIS RENAULT, 01-311mm:couar, amen.

SELF-PROPELLED vnnrcnz.

Application flled Api-il 1 1924, Serial No. 708,388, and. inl'rance Kay19, 1988.

The present invention relates to improvements in self propelled vehiclesequipped with two rear driving axles and two sets .of driving tyresarranged in tandem, and pertains to the use of a flexible endless trackband for facilitating travelling over soft or sandy ground.

The flexible endless band for travelling over sandy ground may be in theform of 10 a skeleton endless track, the cross section of "which isdesiglned in such a way as to exactly fill up t e gap between the twotwin E ves, and the exterior surface of which'is ush with the two tyretreads, which it thus joins together into a single wide surface, thusgiving to the vehicle a wide grip on the ground.

In the accompanying drawing Figure 1 is a side view of the back part ofthe vehicle provided with the'improvements according to the invention.Figure 2 is a back view of the same vehicle, certain parts beingomitted; Figures 3 and 4 are sections through the axis of a set of twinwheels.

28 The underframe 1 of the vehicle has at the back two driving. axles2-3. The former receives motion from the en ine, for example by meansof. a Gardan sha 4 coming from the change speed gear box. This 30 firstaxle transmits motion to the second one by means of a chain 5.

These two axles are integral with springs 6, attached at 7 to theunderframe 1 by any suitable means.

The transmission shown is given only by way of example; there might beprovided any other known means of transmission used on vehicles with sixwheels or sets of wheels, the four back wheels of which are drivingwheels. y The arrangement, which constitutes more particularly thesubject of the. invention, consists in attaching twin pneumatic tyres oneach of the driving wheels of the vehicle.

Such a vehicle on roads, or even on tracks ofvcomparatively solidground, could attain normal commercial speeds, and the surface incontact with the ground will be much greater with this set of fourwheels with 60 twin tyres, than in thecase ofa vehicle having only asingle driving axle, or even of a veh1cle with six wheels, the fourdriving :vheels of whichare provided with single yres.

The invention consistsfurther in adding to these sets of twin wheels fordifiicult travelhng on loose ground, an endless track band 8providedwith wedges 9, which is attached to these wheels. The wedges '9 fit inbe tween the inner sidesof the tyres 10 of the twm wheel.

This flexible band may be made of elastic material.

The adhesion of these bands. to the tyres will be suflicient, with thematerials used,

assummg that all the wheels, which they envelope, are driving wheels. Itis to be clearfrom getting in between the tyres.

It will be obvious from an examination of the draw ng, that thisarrangement increases the tread surface or the surface in contact withthe ground.

The flexible band will preferably be made of material-identical wit thatof the tyres,

'in order to render the wear uniform, andto maintain the continuity ofthe supportm surface.

claim:

In a self propelled vehicle equipped with a parallel axle double reardrive, the'combination of two sets of; driving tires arranged in-tandem,eachset being madeup of a plurality of laterally adjacent tires, and

the endless bands,

a removable endless belt between and supported by the adjacent side ofeach set of tires, and frictionally driven thereby, the outer surface ofthe belt being substantially flush with the tire treads.

In testimony whereof I afiix my signature LEON SAIVES.

